Field of the Invention
This invention relates to the technology field of light sources for illumination and display, and in particular, it relates to a projection system, a light source system and a light source assembly.
Description of Related Art
Projectors are widely used for movie playing, conferences, advertisement, and other applications. It is well known that light sources for projectors commonly uses a phosphor color wheel to generate a color light sequence. The different color segments of the phosphor color wheel are sequentially and periodically disposed on the propagation path of an excitation light; the excitation light excites the phosphor materials on different segments of the phosphor color wheel, to generate different color fluorescent lights (converted lights). However, because the spectral ranges of the color lights generated by the phosphor materials are relatively broad, some of the fluorescent lights have insufficient color purity. As a result, the color gamut of the light source is not sufficiently large. In such situations, filters are typically used to filter the fluorescent lights to improve the color purity of the lights. However, because the spectra of the fluorescent lights of different colors have partial overlap, it is difficult to use one filter plate to filter such lights. Thus, different filter plates corresponding to different colors of fluorescent lights need to be provided. In a solution provided by one conventional technology, a filter wheel is provided at the entrance of a light homogenizing rod; the filter wheel is driven to move synchronously with the phosphor color wheel by controlling the drive devices of the phosphor color wheel and the filter plate color wheel, using a control electrical circuit. Such devices have problems such as complex structures, difficult to realize, and poorly synchronized movements.